But reading through some of the comments online, it seemed clear that some saw the story through a very different lens - another tale of Jewish wealth and privilege, as though every Jewish family in pre-war Europe owned a Picasso or a Matisse. And as though anyone who now came forward to claim ownership was greedily depriving the public of works that rightfully belonged in museums.

So, maybe not such a triumph over Nazism after all?

The more I read, the more I found myself thinking about my own family's history. And my own obsessive interest in finding out what had survived the war - and what had been lost.

Mendel Szpiro was my teacher...

"Before his attempt at suicide he wrote his last will and bequeathed to me, his beloved pupil, his library, which he had collected over 50 years. This was his soul, his dearest possession which he left to me."

David Wdowinski, And We Are Not Saved (1985)

My mother's family were Polish Jews, rooted for centuries in a land they knew intimately and considered home.

I thought of my great-great-grandfather, Menachem Mendel Szpiro.

He grew up a devout Hasidic Jew, but as a young man he cut off his sidelocks, trimmed his beard and embraced a world of secular knowledge.

He set up a school for girls and became a renowned educator and a passionate linguist.

Already fluent in Yiddish, Hebrew, Polish and Russian, he sat at his kitchen table late into the night, teaching himself Esperanto by candlelight, then Spanish, French and German.

His small apartment was crammed with books on all subjects - a library built up over 50 years.

The books are long gone. Aged 78, Menachem Mendel attempted suicide in the Warsaw Ghetto, failed, and ended up dying in the Treblinka death camp.

I only know about the library because I found a description of it in a memoir by a former pupil of his who survived the war.

That's a much more typical wartime story than the miraculous survival of some valuable paintings.

I thought of another relative, my cousin Paul, who I first met in Boston when he was in his sixties.

Paul was a tough, plain-speaking sort of guy - a survivor of the war, and of life in general. He was the first adult I ever met with a concentration camp number tattooed on his arm.

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He had made a new life for himself in the United States. But his most treasured possession was a single, torn-off cover from an old round fob watch.

He unwrapped it proudly to show me. It was engraved with a photographic portrait of his grandfather, Moyshe Asch, the family patriarch, who had given all his 10 children an identical watch.

Nine of the watches disappeared over time. But at the age of 20, Paul had torn the inner cover off his watch and hidden it inside a window sill in his home in the Polish city of Lodz, before he was deported.

He returned as a liberated survivor, persuaded the new occupants of his home to let him in, and retrieved the sliver of metal from its hiding place.

It's these stories, not the headline grabbing news of long-lost paintings, that are the stuff of modern Jewish history. And not just Jewish history.

World War Two was a time of rupture, loss and uprooting on an epic scale.

Family links were torn apart, extended family networks accumulated over generations swept away. And along with the people, a world of possessions, heavy with the weight of memory and meaning.